Mercedes-Benz C-Class 2014 Owner's Manual page 419

Battery (vehicle)
416
Charging the 12 V battery
G WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery.
G WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with
water and seek medical attention.
G WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases
can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only charge the battery using the jump-
start connection point.
The jump-starting connection point is in the
engine compartment (
Open the bonnet.
X
Connect the battery charger to the positive
X
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure (
Never charge the battery if it is still fitted to
the vehicle, unless you use a battery charger
which has been tested and approved by
Mercedes-Benz. A battery charger unit spe-
cially adapted for Mercedes-Benz vehicles
and tested and approved by Mercedes-Benz
page 418).
Y
page 418).
Y
is available as an accessory. This device per-
mits charging of the battery in position. Con-
tact a Mercedes-Benz Service Centre for
information and availability. Read the battery
charger's operating instructions before
charging the battery.
If the indicator/warning lamps do not light up
at low temperatures, it is very likely that the
discharged battery has frozen. In this case
you may neither jump-start the vehicle nor
charge the battery. The service life of a bat-
tery that has been thawed may be reduced.
The starting characteristics may be impaired,
especially at low temperatures. Have the
thawed battery checked at a qualified spe-
cialist workshop.
Hybrid vehicles: if the battery charge is suf-
ficient, the high-voltage battery can also sup-
ply the 12 V battery with energy. This only
happens if the battery charge of the 12 V bat-
tery requires this, e.g. after using electrical
consumers for an extended period with the
engine switched off. As the on-board voltage
is continuously monitored this can also be
performed when the engine is switched off.
The battery charge of the 12 V battery and the
on-board voltage are thereby kept stable for a
longer period.
Charging the high-voltage battery
when stationary
Only hybrid vehicles are equipped with a high-
voltage battery.
WARNING
G
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
! Only charge the high-voltage battery in
the "Charging when stationary" operating
mode. Do not connect a battery charger to
the high-voltage battery. Otherwise, the